Seiffert means, asymptotic expansions and related inequalites

Sa？etak In this paper we study inequalities of the form (1 - μ) M1(s, t) + μ M3(s, t) ≤ M2(s, t) ≤ (1 - ν) M1(s, t) + ν M3(s, t), which cover some classical bivariate means and Seiffert means. Using techniques of asymptotic expansions detailed analysis was made and the method for obtaining optimal parameters μ and ν was described